Art of grinding cutting edges



F. H. PERRY. ART OF GRINDING CUTTlNG EDGES.

APPLICATION FILED AUG- 21, 1917.

1 ,4003'61 Patented Dec. 20, 1921.

2 SHEETS-SHEET 1.

WWWJE I F. H. PERRY.

ART OF GRINDING CUTTING EDGES.

APPLICATION FILED AUG.21,1917.

Patented Dec. 20, 1921..

2 SHEETS-SHEET 2.

arias FREDERICK PERRY, 011 BEVERLY, ItIASSACHU-SETTS, ASSIGNOR, BY

IVJIESNE ASSIGN- MENTS, T0 UNITED SHOE MACHINERY CORPORATION, OFPATERSON, NEW JERSEV A CORPORATION OF NEW JERSEY.

ART OF GRINDING CUTTING EDGES. I

Monger.

Specification of Letters Patent.

Patented Dec. 20, 1921.

Application filed August 21, 1917. Serial No. 187,402.

of Beverly, in the county of Essex and State of Massachusetts, haveinvented certain Improvements in the Art of Grinding Cutting Edges, ofwhich the following description, in connection with the accompanyingdrawings, is a specification, like reference characters on the drawingsindicating like parts in the several figures.

This invention relates to the sharpening or grinding of cutting edgesand more particularly those of cooperating knives of clifferent formsuch as are used, for example, in jointing machines for trimming theedges of the shanks of shoes. In machines of this class there are, asfully explained in my Patent No. 1,080,605, dated June 25, 1912, areciprocating trimming knife, having opposite cutting edges, whichoperates upon the inner and outer edges of the shank portion of a shoeto give it the proper outline, and corresponding knives, called choppingknives, which reciprocate parallel to the breast of the heel, serving toout off the chips left by the trimming knife. As has been pointed out inthe previously mentioned patent, the trimming and chopping knives, whiledifferent in form, must have one contour common to both to enable thechopping knives to just sever the curved chips of the trimming knifewithout cutting into the shank. This common line lies along the edges ofthe trimmingknife, as viewed longitudinally of the body, and along theedges of the chopping knives, seen laterally. Obviously, if these edgesare to cut to precisely the same points throughout their lengths, theymust be so ground as to preserve always this identity of contour. Animportant object of this invention is the provision of an improvedmethod Whereby one of a plurality of cooperating knives may be so groundthat in their use they will out along their entire edges, point forpoint, to a common line, and, moreover, that this relation shall bemaintained as both knives are ground. This object is attained byemploying a templet, for example, one of the knives, to provide a guidefor grinding another. Thus, in sharpening the knives of a jointingmachine, the edge trimming knife may serve as a templet or in theformation of such a templet for the chopping knives.

The invention also provides novel apparatus by which my improved methodmay advantageously be carriedinto effect. In this a support for theknife or knives to be sharpened and a grinding surface, as the edge of arotatable abrasive Wheel, are movable relatlvely to subject the entirecutting edge to the grlndmg action, and the cooperating knife isutilized to determine the path of this feeding movement.

Since some machines,as the jointing mach nes previously referred to,employ two knives operating upon opposite sides of the work, it isdesired to furnish means for qulckly and conveniently arranging-for thegrinding of both knives. In the illustrated apparatus this is attainedby using a single templet, as the trimming knife of the joint mgmachine, for grinding both the cooperatmg knives,'this templet beingmovable, pref erably by reversal, afterone knife has been ground to aposition to adapt it for the grinding of the opposite knife. By suitableconnections between the templet and knife support the preparation of thecooperating elements to grind the second knife may be and as shown aremade automatic.

Various other features are embraced by my invention as will be madeevident by the following description and claims.

In the accompanying drawing- Figure 1 is a side elevation of oneembodiment of my improved apparatus, shown in position upon a portion ofthe frame of the machine to which it maybe attached, the latter being insection;

Fig. 2 is a perspective view of the grinding apparatus;

Fig. 3 is a partial top plan view of the knife-holding and guidngelements. and

Fig. 4 is a detail perspective of a portion of the connections forshifting the stops.

Upon the frame 10 of a machine, the knives of which are to be ground, issecured a bracket 11 furnishing a support for the active elements of theapparatus of the present invention. This bracket carries a table 12 fromwhich rises a standard 13 having journaled in itthe shaft 14; of asuitable grinding wheel 15. Fast upon the grinding wheel shaft isapulley 16 which may be driven by belt gearing from a shaft uponthemachine to which, the grindingapparatus is attached- 45 the knivesCand Dginto, contact with the Depending from the under side of the table12 are projectlons 17 having formed .in their inneredges ways to receivea slide 18. At the rear of the slide 18 is a lug 19 in which isrotatably mounted a screw 20 threaded into an enlargement beneath thetable. Carried upon'the front face of the slide are blocks 21, 21 inalined bores in which is mounted a guide rod 22 having a limitedlongitudinal movement, as will hereinafter appear. Movable upon the rodare bearing members 23, 23 joined by a curved yoke 24 and carrylng asupporting arm 25 whichextends upthrough an openj in position.

jing- 26 in the table 12. The arm 25 carries at its upper extremity aknife holder 27 in which are two vertical slots 28, 28 lying adjacentand parallelv to one another and having at their tops pairs of ways 2929v to receive the shanks of' the knives to be ground. 'A screw 30passing through, an.

opening in the holder below the ways and being threaded into the fartherside serves to draw the ways together and thus gives a common means forclamping both knives be ground have oppositely curved cutting ;edges'0and (Z which enable them to work upon the right and left sides of theshoe shanks These knive's,fwhen fixed in the ways'in'the holder, maybeso positioned that their adjacent cornerslie just at the opposite edgesof the grinding surface of the wheel'l5. To determine the length of thepaths through which the knives are moved in their grinding,-stops areprovided consisting of screws 31, 31 threaded through arms 32, 32secured to the ends ofthe guide rod 22. The knife holder is limited inits movement away from the grinding wheel as the arm'25 is turnedaboutltherod 22 by contactofthe arm withthe outer edge of the opening:26 in the table 12, and may be swung therefrom to bring the edges ofwheel. To allow free inspection of the knives during their grlnding theknife holder 27 is pivoted upon the arm 25 by means of a screw 33 and islocked in normal position by a'spring-pressed piu'34 entering an openingin the face of the boss upon which the holder turns.

From one side of thearm 25 projects a branch arm 36 carrying a holder 37in the form of a crank disk for the templet by which. the choppingknives C and. D are to be guided in the desired paths over the grindingwheel. In accordance with the illustrated embodiment ofmy invention,

this templet is furnished by a trimming "knife T which cooperates in thejointing machine with the chopping knives. fit-the outer edge of thecrank d sk is an angular portion provided in its inner face with dove-In the present instance, the chopping knives C and D which are to;

1 ,eoonev tail ways 38to receive the correspondingly formed portion ofthe trimming knife shank, the knife being secured in theuvays by'aclamping screw 39. At the. rear of this templ'et' is a guide memberfurnished by the point of a screw 40 which is threaded through the upperend of an arm 41 secured to the front face of the 'slide 18. The endof'the arm through which the screw 40 passes is slotted, the portionsbeing drawn together by a screw 42 to fix the guide screw againstrotatlon. The screw 40 153 so ad usted through 1ts arm wlth respect tothe templet that when the latter is in contact with the point of thescrew the knife holder will be moved sulficiently'near to the edge ofthe grinding wheel to remove thev desired. amount of material from theknives C and D. As the support is slid longitudinallyrupon the rod 22the engage ment between the point of the guide screw and templet willcause the holder to describe a path exactly correspondingto said templetand therefore cause the chopping knife to be ground to the precisecontour line of the trimming knife. The screw 20, previously describedas cooperating with the lug upon the, slide 18 enables the user of theapparatus to. change the vertical position of the kmves C and D withrespect to the grinding wheel, thus permitting the use of wheels ofdifferent diameter. an adjustment of this screw, in connection with analteration in the positioniof the guide screw 40, changes the angle atwhich the knives are presented to the grindingwheel and therefore thebevel at which they are ground. v

To enable the operator to. grind both knives with the same templet, thetemplet holder is'preferably mounted upon. apivot pin 48 the axis ofwhich is in alinement with theaxis of the guide screw. Fast upon the pin43 with the holder dlsk is an arm 44 carryingat its outer extremity aspring,

pressed pin 45, which may enter a. hole 46 atone end of a segmentalsurface at the top of the branch arm 36 or a corresponding hole at theopposite end of the segment with i will be reversed, it now directingthe guide screw 40 along its curved surface to the left instead of totheright to provide for the gr nding of theother kn fe D having theopposite curvature. At thesame timeitae templet is reversed, the stops31, 31 are preferably automatically adjusted to fix the limits of thepath through which the particular knife to be ground is to move.Projecting from the inner side of the holder disk 37 is a pin l7 havinga ball head furnishing a universal connection for a rod 48, which at itsother end is articulated upon a like pin 49 projecting from the upperarm 50 of a bell crank lever pivoted at 51 upon the slide 18. The lowerarm 52 of the bell crank carries a pin 53 entering a circumferentialgroove 54 near the center of the rod 22. As the templet is reversed, asby moving the pin 45 from its illustrated position into engagement withthe hole t6, the pin 47 on the templet-holding disk is moved f om itsuppermost to its lowermost position, causing the connecting rod d8 toswing down the arm 50 of the bell crank lever and carry the pin 53 tothe right. This, engaging the slot 54;, moves the rod 22 through thebearing members 23 so that the stop screws 31 are positioned to providefor a travel of. the knife support upon the rod from the righthandcontact screw to that at the left and fix the limits of the feedingmovement of the knife D as was provided for in the case of the knife Cwith the stop pin 45 in engagement with the opposite hole.

In the performance of my novel method by the use of the apparatusdescribed both the chopping knives of a jointing machine are clamped inthe holder 27 with their adjacent corners in the same transverse lineand the trimming knife with which the chopping knives are to cooperateor a templet constructed therefrom is introduced into the holder 37.Then the apparatus is adjusted by means of the screw 20 and the guide srow 40 to give the proper relation of the edges to be ground to the edgeof the wheel and to produce the desired bevel. With the pin f?) in oneof the holes in the segment, the support 25 is moved along the rodbetween the stops to grind one of the knives. This having beenaccomplished, the trimming knife which is being used as the templet isreversed by carrying the pin 45 into the other hole in the segment andthe companion chopping knife similarly ground.

Having thus described my invention, what I claim as new and ters Patentis 1. The method of sharpening upon an abrasive surface one of aplurality of curved knives having cutting edges of different form, whichconsists in supporting one knife in a grinding position, holding theother knife at an angle to the first, and moving the knives together topresent the edge of the first knife to the abrasive surface whileutilizing the transverse contour of the second knife as a guide.

2. The method of sharpening a pair of desire to secure by Let oppositelyformed knives which in use 00- operate with another knife tocut tocommon lines which consists in employing the lastnamed knife as atemplet in grinding one of the pair of knives and then reversing thetemplet in grinding the other knife of the pair.

3. In an apparatus for grinding one of a plurality of cooperatingknives, a grinding member, a support for one of the cooperating knives,said member and support being relatively movable to permit the fee'd ofthese elements by one another, means including a guide in the form ofanother of said knives for determining the path along which this feedingmovement shall occur, and means controlled by the guide by which thelength of said path may be variably determined.

4;. In an apparatus for grinding one of a plurality of cooperatingknives of different form, a grinding member, a support for one of thecooperating knives, said member and support being relatively movable topermit the feed of these elements by one another, a second support forholding the other of the cooperating knives in a plane substantiallperpendicular to the plane of the first-mentioned knife, whereby saidfeeding movement follows a path corresponding with the profile of thelast-mentioned knife, and means for mounting the supports forangularmovement with respect to the grinding member.

In an apparatus for grinding one of a plurality of cooperating knives ofdifferent form, a grinding member, a support for one of the cooperatingknives, said member and support being relatively movable to permit thefeed of these elements by one another, a second support for holding theother of the cooperating knives in a plane substantially perpendicularto the plane of the first-men tioned knife, whereby said feedingmovement follows a path corresponding with the profile .of thelast-mentioned knife, and means for holding said path-determining knifein a plurality of positions to adapt it for grinding different knives.

6. In an apparatus for grinding one of a plurality of cooperatingknives, a grinding member, a support for one of the cooperat ing knives,'sa-id'member and support being relatively movable to permit the feedofthese elements by one another, means including another of said knivesfor determining the path along which this feeding movement shall occur,means for holding said pathde termining knife in a plurality ofpositions to adapt it for grinding different knives, and meanscontrolled by the position of the pathdetermining means for presentingdifferent knives to the grinding member. s

7. In an apparatus for grinding one ofa plurality of cooperating knives,a grinding member, a support for one of the cooperating knives, saidmember and support being n 1 relatively movable to permit the feed orthese elements by one another, means including the tr nsverse side faceof another of said knives for determining the path along which thisfeeding movement shall occur, and

. means for holding said pathedetermining knife in reverse positions toadapt it. for grinding oppositely formed knives.

' 8.111 an apparatus for grinding one ofa plurality of cooperatingknives, a grinding member, a support for one of the cooperating knives,said memberan d support being relatively movable to permit the feed ofthese elements by one another, means 1ncluding another of said knivesfor determnnng the path'along which this feeding movement shall occur,means for holding said path-determiningknife 1n reverse positions toadapt 1t for grinding oppositely formed knives,

. and means controlled by the position of the path-determining means forpresenting one 'or theother of the knives to the grinding member;

9. In an apparatus for grinding one of a plurality of differently formedcooperating knives-adapted for different cutting operations, a grindingmember, a support for the :knife tobe ground, said member and supportbeing ,relativelymovable to permit the feed of these elements by oneanother, a holder constructed and arranged'to receive one of thedifferently operating knives and support it in a plane substantiallyperpendicular to the plane of the knife to be ground, and meanscooperating with the last-named knife to guide thefeeding movement.

10. In an apparatus for grinding one of a V plurality of differentlyformed cooperating knives adapted for different cutting operations, agrinding member, asupport for the knife'to be ground, saidmember andsupport being relatlvelymovable to permit the feed of these elements byone another, a

holder constructed and arranged to receive one of the differentlyoperating knives and support it in a plane substantially perpendicularto the plane of the knife to be ground, and means cooperatin with thelast-named knife to guide the feeding movement, said means and guideknife being relatively adjustable toward and from one another.

, 1 1. In an apparatus for grind ng the chopping knives of machines foroperating upon the shanks of shoes by trimming kn ves, a

grinding wheel, a support for the chopping knife and a reversiblesupport for a shanktrimming knife movable together, and a membercooperating with the trimming knife for guiding the chopping knife overa the wheel.

12. The combination with i a grinding wheel, ofa support provided withmeans for mounting thereon a plurality of knives to be ground a movabletemplet, guiding means contacting with the transverse surface or profileof the templet, and means operable in the movement of the templet forpresenting different knives; to the grinding wheel.

13. The combination with a grinding .templet, a stop for the support,and connections operable in moving the templet for changing the positionof the stop.

15. The combination with a. grinding wheel, of a support provided withmeans for clamping thereon oppositely formed knives to be ground, atemplet holder pivoted upon the support, a guide point situated inalinegient with the pivotal axis of the templet holder, andconnectionsoperable in swinging the templet. about its pivot for changing therelation of the knives to the grinding wheel.

16; In a grinding apparatus, the combination with a frame, of a grindingwheel rotatable thereon, a support movable in the frame and beingprovided with means for clamping thereon oppositely formed knives to beground, a movable stop for the support, va templet holder pivoted uponthe support, a guide for cooperation with the tem-' plet, a leverfulcrumed upon the frame, connections between the templet holder andlever, and means cooperating with the lever to rock it in the movementof the holder to move the stop and'thereby adapt the apparatus forgrinding theknife other than that 7 previously ground.

17 In a grinding apparatus, the combination with a frame, of a grindingwheel rotatable thereon, a movable support, a guide rod therefor, aknife holder-situated adiacent to the grinding wheel and beingpivoted'upon the support, means for fixing the knife holder in differentangular positions with respect to the grinding wheel, a templet holdercarried by the support, and a guide for cooperationwith the templet.

18. In a grinding apparatusthe combination with a frame, of a grindingwheel rotatable thereon, a movable support, a holder provided with pairsof grooves, means c0mmon to the pairs of groovesfor clamping two knivesto be ground, atemplet usable in grinding either knife, and a: guidemember for cooperation with the templet.

19. In a grinding apparatus, the combination with a frame, of a grindingwheel r0- tatable thereon, a movable support, a guide rod therefor,stops carried by the guide rod at opposite sides of the support, a knifeholder and a templet holder carried by the support, and a guide memberfor contact with the templet,

20. In a grinding apparatus, the combination with a frame, of a grindingwheel rotatable thereon, a guide rod provided with a groove, a stopcarried by the guide rod, a support movable along the guide rod, a knifeholder fixed to the support, a templet holder pivoted upon the support,a lever fulorumed on the frame and having a projection engaging thegroove in the guide rod, connections etween the lever and templetholder, and a guide member for contact with the templet.

21. In a grinding apparatus, the combination with a frame, of a grindingwheel rotatable thereon, a guide rod providedwith a groove, a stopcarried by the guide rod, a support movable along the guide rod, a knifeholder fixed to the support, a templet holder pivoted upon the support,a lever fulcrumed on the frame and having a projection engaging thegroove in the guide rod, connections between the lever and templetholder, a guide member for contact with the templet, and means forfixing the templet in either of two extreme positions.

22. The combination with a grinding wheel, of a support provided withmeans for mounting thereon a plurality of knives for operating atdifferent angles, and means for varying the position of the support withrelation to the grinding wheel to correspond to the operating positionsof the knives.

In testimony whereof I have signed my name to this specification.

FREDERICK H. PERRY.

